The purpose of thinking about the future is not to predict it but to raise people's hopes.

The idea that global warming is the most important problem facing the world is total nonsense and is doing a lot of harm.

All stable processes we shall predict. All unstable processes we shall control. Describing John von Neumann's aspiration for the application of computers sufficiently large to solve the problems of meteorology, despite the sensitivity of the weather to small perturbations.

Everything in my life was luck. The key to having an interesting life is to always say "yes" to anything crazy.

We have no reason to think that climate change is harmful if you look at the world as a whole. Most places, in fact, are better off being warmer than being colder. And historically, the really bad times for the environment and for people have been the cold periods rather than the warm periods.

Most of the crackpot papers which are submitted to The Physical Review are rejected, not because it is impossible to understand them, but because it is possible. Those which are impossible to understand are usually published. When the great innovation appears, it will almost certainly be in a muddled, incomplete and confusing form. To the discoverer himself it will be only half-understood; to everybody else it will be a mystery. For any speculation which does not at first glance look crazy, there is no hope.

Walking the streets of Tokyo with Hawking in his wheelchair ... I felt as if I were taking a walk through Galilee with Jesus Christ [as] crowds of Japanese silently streamed after us, stretching out their hands to touch Hawking's wheelchair. ... The crowds had streamed after Einstein [on Einstein's visit to Japan in 1922] as they streamed after Hawking seventy years later. ... They showed exquisite choice in their heroes. ... Somehow they understood that Einstein and Hawking were not just great scientists, but great human beings.